The invention relates to a magnetorheological fluid shock absorption buffering device under an extrusion mode. The device is mainly used for static contact shock absorption buffering in the aspects of buildings, bridges, heavy machinery equipment and the like. The device mainly comprises a connection bolt, a cover plate, a connection nut, a magnetic conducting outer barrel, a magnetorheological fluid, electromagnetic coils, a bottom plate, an isolation ring, a fixed block magnetic conductor, a movable block magnetic conductor and a movable block magnetic isolator. According to the invention, a buffered object is connected with the buffering device through the connection bolt, and a certain current is charged into the electromagnetic coils, thus a closed magnetic field is formed among the magnetic conducting outer barrel, the fixed block magnetic conductor, the movable block magnetic conductor and the magnetorheological fluid; and the magnetorheological fluid forms an extrusion shear yield stress in the direction of the magnetic field, and when a pressure is applied in the outside, the magnetorheological fluid generates elastic deformation and plays a shock absorption role on the outside. The device has a high compressive elastic modulus; and under the extrusion mode, the static displacement of the magnetorheological fluid is reduced with the increase of the applied current, therefore, higher bearing capacity and frequency shift characteristic are achieved.